by making it easier for users to post on your forum is the absolute goal. saying if they can't post they shouldnt post in the first place, is the wrong way to think about it. email is a valuable tool to use in a board. it won't turn your board into a mailing list, it will just give an option to the user/users to post/reply by email. this option in my eyes is soo really cool.
i heard some of my friends complaining that when there users post gets replied to they just push reply on the email and send the message that way. if you could just push reply in yoru email and press send, the message gets posted and you don't have to open up your netscape. that rocks.
again , most people won't be able to use this option cause you would have to forward your mail to a script, and not many hosts allow that.
i would love to do something like this to work with phpnuke, to post articles by mail.

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